Q: I have an XY scatter chart that gets divided into 4 quadrants with each quadrant needing a different color. Any ideas?

A: See Below.

First we'll build a chart with just the background quadrants. We'll use a stacked column chart for this. I constructed some dummy data which will give you quadrants exactly half the chart high and half the chart wide.

1      0      1      0
0      1      0      1

Start with the dummy data, select it and construct a stacked column chart, plotted by column.

Select one of the series, right click >Format > Options tab, and set the Gap Width to 0.

Select the Y axis, right click > Format > Scale, set the maximum to 2, and set Category Axis Crosses at Maximum.
Select the X axis (top of chart), right click > Format > Scale, and set Value Axis Crosses at Maximum.

Format each of the column series in a color you like, and set borders to None.

Now we're ready for the Real data. Select and Copy the data range, select the Chart, Edit menu > Paste Special, Paste as New Series, Categories in First Column, Series Names in First Row.

Looks like we spoiled it, but let's plod along. Select the series you just added, right click > Chart Type, and pick one of the XY Scatter styles. With the series still selected, right click > Format > Patterns, and format it the way you like.

Select the top X axis, right click > Format > Patterns, set Major Ticks, Minor Ticks, and Tick Labels to None; Repeat for right side Y axis. You can kill the legend, or one by one, select and delete the legend entries for the four quadrants.

ColoredQuadrantBackground.zip is a zipped Excel file with an easy demonstration of these steps. A more advanced technique, which allows greater control over the number and sizes of the background shaded regions, is explained in my Tech Trax article on Matrix Charts.

This stacked area chart technique can be combined with XY series to display points amidst a map of different chart regions. This chart's XY series use custom XY markers (circles with arrows) that show relative market growth within each industry segment: